AOPA supports WAAS for NextGen navigation

March 8, 2012

ByJim Moore

The FAA has presented a broad outline of a future national airspace with half of the current VOR network decommissioned by 2020, and AOPA is urging the agency to make sure GA pilots—and current equipment—have a place there.

AOPA has long supported the concept of satellite (performance-based) navigation, a system built on GPS signals and RNAV that will allow safe, point-to-point navigation—even in instrument meteorological conditions. The FAA must also plan a backup system that is able to function in case of satellite outages. In a Feb. 5 letter, AOPA Vice President of Air Traffic Services and Modernization Heidi Williams urged the FAA to utilize existing GA equipment for the alternative position, navigation, and timing (APNT) system, and not rely on solutions based on distance measuring equipment (DME) technology that has become uncommon in the GA fleet.

Williams, in the association’s response, said the 74,000 WAAS unit sales to date demonstrate that GPS has been embraced, and must be carefully protected.

“AOPA strongly encourages the FAA to ensure safeguards exist that allow for continued and reliable GPS coverage, including perimeters around the range and scope of planned jamming and tests, and assurances against interference by other spectrum users,” Williams said. “Clearly, these safeguards will require cross-governmental agency coordination and collaboration to adequately protect GPS reliability and viability.”

AOPA urged the FAA to avoid wholesale replacement of the current Victor airway network with T-routes, and instead utilize the point-to-point navigation capabilities supported by WAAS and RNAV whenever possible.

While AOPA recognizes the cost savings that will come, Williams noted many important details about the planned reduction from 954 to 483 VOR stations remain unknown, including details about impacts to navigation below 5,000 feet agl. It remains unclear how the transition will affect availability of instrument approaches, departures, or navigation at lower altitudes.

“In particular, pilots must be afforded the opportunity to comment on any individual reduction in infrastructure after having seen the full VOR MON plan and its associated impacts,” Williams wrote. “We would strongly urge the FAA to establish a portion of their website where the public and aviation community could stay abreast of any proposed navaid decommissionings and have an opportunity to provide input.”